Entry Date:
December 7, 2006

Models and Analysis for Ship Breaking Waves

Principal Investigator Alexandra Techet

Co-investigators Dick Yue , Kelli Hendrickson


Accounting for the effects of breaking waves, spray formation and air entrainment on the performance and non-acoustical signature of a surface ship is one of the main remaining challenges in modern naval ship design. As the ship design requirements shift to higher Froude numbers and novel hull concepts, useful experimental data are becoming scarce and expensive to obtain, and the Navy will be increasingly reliant on numerical simulations in the design and analysis process. Currently, large-scale CSH applications such as Euler codes, URANS codes, and potential flow codes are being pushed to the limit in terms of their capabilities in simulating the highly-complex flow and free-surface phenomena associated with ships in waves.

In the development of wave breaking models, we have utilized robust direct numerical solvers to obtain a large ensemble of high resolution datasets for small-scale breaking waves. These benchmark datasets provide a strong foundation for the understanding of the underlying physics of ship breaking waves. In particular, we are able to quantify the energy dissipation, vorticity production and transport, and the transfer of energy across the air-water interface for different types of breaking waves. With this knowledge, we are able to develop: (i) analysis of RANS turbulent kinetic energy (TKE) equation to understand the relation of production, transport and dissipation in the context of ship breaking waves; (ii) analysis of (new) interfacial RANS terms which are associated with transport at the air-water interface; (iii) development of SGS and RANS closure models for these terms; and (iv) analysis of existing and new RANS models to evaluate their applicability and efficacy for ship breaking waves.